Magento vs Vetcove vs Covetrus Marketplace vs Shopify for vet supply, which wins?

Honest cut, vet-supply-specific:

• Vetcove is a buying co-op, vet clinics use it to compare prices across distributors. Great as a clinic-side tool, useless as a distributor-side storefront. You don’t build on Vetcove, you list on it.
• Covetrus Marketplace is a closed channel owned by Covetrus (one of the four big distributors). Listing here puts you in competition with Covetrus’s own SKUs at their margin. Fine as a secondary channel, terrible as your only storefront.
• Shopify works for tiny vet-supply resellers (under 1,000 SKUs, no DEA, no cold-chain). Hits walls fast: variant ceiling (100 per product), no native customer-segment B2B pricing, no practice-management integration, no DEA workflow, no cold-chain shipping rules. App-based workarounds exist but accumulate to $800-$2,500/mo and still don’t handle CSOS.
• Magento wins for any distributor at 10,000+ SKUs serious about owning the customer relationship. Practice-management integration (Cornerstone, AVImark, ezyVet, Provet Cloud) is the moat that Vetcove can’t copy, once you’re wired into a clinic’s PIMS for one-click reorder, switching costs spike. DEA workflow, cold-chain rules, customer-segment B2B pricing, multi-region all native.

Most vet-supply distributors I work with run Magento as the order-of-record and list a curated subset on Vetcove + Covetrus Marketplace as discovery channels.